目的 通过三维立体摄影测量术对上颌扩弓患者面部软组织进行分析。 方法 对11例需要进行上颌扩弓治疗的患者进行研究。拍摄患者三维面部照片，对面中部及嘴唇的宽度，脸颊、八字纹处及嘴唇的面积和体积进行测量，分析正畸患者上颌扩弓后面部软组织变化情况。 结果 面中部曲线宽度在正畸治疗前为（269.24±49.60） mm，在上颌扩弓治疗后为（322.54±28.94） mm，对比术前明显增大（P=0.005），脸颊面积及体积无明显变化（P>0.05）。面下部软组织在上颌扩弓前后无明显变化（P>0.05）。不同部位的左右面部测量对比显示上颌扩弓对于左右面部软组织的改变差异无统计学意义（P>0.05）。 结论 上颌扩弓会造成面中部宽度增大，而对脸颊面积和体积、面下部软组织无显著改变，左右面部软组织的变化不具差异性。

Objective To evaluate the changes in facial soft tissue after maxillary expansion through stereophotogrammetry. Methods Eleven patients undergoing maxillary expansion were studied. Three-dimensional photographs of the face were taken to measure the widths of the middle face and lips as well as the areas and volumes of cheeks，nasolabial folds，and lips for analyzing the changes in facial soft tissue after treatment. Results After maxillary expansion，the curve width of the middle face was increased significantly ［（269.24±49.60） mm vs. （322.54±28.94） mm，P=0.005］；there were no significant changes in the area and volume of the cheeks and the soft tissue of the lower face（P>0.05）；the changes in the soft tissue of different parts between the left and right faces were not significantly different（P>0.05）. Conclusion Maxillary expansion can increase the curve width of the middle face，with no significant changes in cheek area and volume and lower facial soft tissue and no significant differences in facial soft tissue changes between the left and right faces.